Eastern North Pacific Tropical Weather Discussion (Text)

000
AXPZ20 KNHC 132113
TWDEP
Tropical Weather Discussion
NWS National Hurricane Center Miami FL
2039 UTC Wed Dec 13 2017
Tropical Weather Discussion for the eastern Pacific Ocean from
the Equator to 32N, east of 140W. The following information is
based on satellite imagery, weather observations, radar, and
meteorological analysis.
Based on 1800 UTC surface analysis and satellite imagery through
2100 UTC.
...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
The ITCZ extends from 06N77W to 05N96W to 10N115W to beyond
11N140W. Scattered moderate isolated strong convection is noted
from 08N to 14N between 114W and 127W.
...DISCUSSION...
OFFSHORE WATERS WITHIN 250 NM OF MEXICO...
Gulf of Tehuantepec: High pressure has weakened north of the
area. This has loosened the pressure gradient enough to diminish
winds below gale force. Winds will further decrease over the next
24 hours, and winds and seas will fall below advisory criteria by
Thursday afternoon. Another brief gale force gap wind event is
possible late Friday night through Saturday morning.
Gulf of California: Winds have diminished below advisory
criteria over the northern Gulf. Winds are expected to once again
strengthen over this area Thu night through Sat.
Elsewhere, NW swell of 7-9 ft will spread across the waters W of
Baja California early Fri through Sat night. Otherwise, gentle
to moderate winds will prevail over the offshore Pacific waters
of Mexico, with seas in the 4-6 ft range.
OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND
WITHIN 750 NM OF ECUADOR...
Strong winds will prevail across the Gulf of Papagayo through
early Fri, then strengthen once again Sat night. Moderate to
fresh N winds will funnel through the Gulf of Panama Thu and Fri.
Mainly gentle to moderate winds and seas of 3-5 ft will prevail
elsewhere over this area the next several days.
REMAINDER OF THE AREA...
High pressure of 1027 mb centered north of the area near 37N130W
extends a ridge southeast to near 20N110W. The pressure gradient
between this area of high pressure and lower pressure in the
vicinity of the ITCZ is maintaining moderate to fresh winds from
N of the ITCZ 20N, and W of 115W. The combination of NW swell and
wind generated NE waves is producing combined seas of 8 to 10 ft
across this area. NW swell has propagated into the NW waters,
with seas near 10 ft over the far NW waters. Seas will peak near
13 ft late tonight into Thursday morning before starting to
subside. The swell will propagate southeast across the forecast
waters over the next several days. By Saturday night, seas of 8
ft or greater will cover much of the forecast area west of 110W.
$$
AL